Catheter access to the left atrium is a fundamental step to numerous transcatheter therapies including catheter ablation of rhythm disorders, diagnostic catheterization in pediatric and structural heart disease, and future treatments for mitral valve and left atrial appendage disease. MRI operation would enable radiation free catheterization and superior image guidance that are expected to enhance clinical outcomes. No MRI safe and conspicuous atrial transseptal needle is commercially available. ?Active? MRI catheter devices contain electronic elements to produce MRI visibility. This topic aims to support the development of an active MRI transseptal needle catheter and accessories.